RENICE(8) |
FreeBSD System Manager's Manual |
RENICE(8) |
NAME
renice —
alter priority of running processes
SYNOPSIS
renice |
priority [ [ -p] pid ...][ [ -g] pgrp ...][ [ -u] user ...] |
renice |
-n increment [ [ -p] pid ...][ [ -g] pgrp ...][ [ -u] user ...] |
DESCRIPTION
The
renice utility alters the scheduling priority of one or more running processes. The following
who parameters are interpreted as process ID's, process group ID's, user ID's or user names. The
renice'ing of a process group causes all processes in the process group to have their scheduling priority altered. The
renice'ing of a user causes all processes owned by the user to have their scheduling priority altered. By default, the processes to be affected are specified by their process ID's.
The following options are available:
-
-g
-
Force
who parameters to be interpreted as process group ID's.
-
-n
-
Instead of changing the specified processes to the given priority, interpret the following argument as an increment to be applied to the current priority of each process.
-
-u
-
Force the
who parameters to be interpreted as user names or user ID's.
-
-p
-
Reset the
who interpretation to be (the default) process ID's.
Users other than the super-user may only alter the priority of processes they own, and can only monotonically increase their ``nice value'' within the range 0 to PRIO_MAX (20). (This prevents overriding administrative fiats.) The super-user may alter the priority of any process and set the priority to any value in the range PRIO_MIN (-20) to PRIO_MAX. Useful priorities are: 20 (the affected processes will run only when nothing else in the system wants to), 0 (the ``base'' scheduling priority), anything negative (to make things go very fast).
FILES
-
/etc/passwd
-
to map user names to user ID's
EXAMPLES
Change the priority of process ID's 987 and 32, and all processes owned by users daemon and root.
renice +1 987 -u daemon root -p 32
STANDARDS
The
renice utility conforms to IEEE Std 1003.1-2001 (“POSIX.1”).
HISTORY
The
renice utility appeared in
4.0BSD.
BUGS
Non super-users cannot increase scheduling priorities of their own processes, even if they were the ones that decreased the priorities in the first place.